Separating highlight vs. hover style on node. fixes #377

![screen shot 2014-05-18 at 21 06 43](https://cloud.githubusercontent.com/assets/5281068/3009478/4b51b9b2-defb-11e3-81d3-73da76307fd4.png)

I like the zoom on highlight, it effectively highlights the "highlight" vs. "hover" state.  However, I'm still not sure if having a funky 4 directional shadow is the best way to separate the one box from another.  

I'm open to the ideas.